ALLEGHENY COUNTY -(WPXI)- A 17-year-old boy is dead after being found in the Monongahela River. Allegheny County dispatchers said the search for the boy began near the Mansfield Bridge at around 8:15 p.m. Friday night. Crews were staged across the river at the 200 block of Washington Avenue in Dravosburg. The Glassport police chief said the boy, later identified by the Medical Examiner’s Office as Benjerman T.N. Coleman, was swimming and fishing with other people when he went under the water and did not resurface. Coleman was pronounced dead at around 1:45 a.m. The people around him quickly called 911. The chief said the river is about 15-20 feet deep. Investigators said Glassport emergency crews were leading the investigation.